Pressure-sensitive adhesives are widely used for masking tapes, double-sided tapes, surface protective films, wrapping tapes, and the like. Hitherto, as pressure-sensitive adhesives, development of organic solvent-free aqueous dispersion type pressure-sensitive adhesives have proceeded from the viewpoints of environmental measure, resource saving, safety, etc., and amounts of the aqueous dispersion type pressure-sensitive adhesives to be used tend to increase. Among such aqueous dispersion type pressure-sensitive adhesives, rubber based aqueous dispersion type pressure-sensitive adhesives are currently used in the most fields because they are limited in selectivity to adherends and are excellent in adhesion at low temperatures. Also, acrylic aqueous dispersion type pressure-sensitive adhesives are widely diffused in place of the conventional rubber based aqueous dispersion type pressure-sensitive adhesives because of their excellent adhesion characteristics and weather resistance (see Patent JP-A-62-221531, JP-A-63-317575, JP-A-5-39468, JP-A-8-104853, JP-A-8-157783, JP-A-10-292162, and JP-A-2000-239633). (The term “JP-A” as used herein means an “unexamined published Japanese patent application”)
On the other hand, for example, the masking tapes mask an adherend during painting or sealing. However, when the surface of the adherend causes dew condensation during the works in the rainy season or at a low temperature in winter, a sufficient adhesion is not obtained at the time of sticking so that a slippage or peeling may possibly be caused, leading to a reduction in workability. Also, even in the double-sided tapes, there are works on the dewing surface, resulting in a problem.
Also, there is disclosed a pressure-sensitive adhesive tape containing a water-soluble polymer as the major component as one exhibiting good adhesion to the dewing surface (see JP-A-8-120251). However, in these conventional pressure-sensitive adhesive tapes, contamination due to low-molecular weight components eluted by water absorption and swelling at the time of peeling, or adhesive residue due to insufficient cohesion occurs, whereby satisfactory results were not obtained.
Moreover, after sticking the pressure-sensitive adhesive tape, the terminal end of the pressure-sensitive adhesive tape may possibly peel off during a period of curing or by window, resulting in a problem.